Interferons are mainly divided into three categories according to their sources:
1, interferon-α (IFN-α)-comes from white blood cells.
2. Interferon -β(IFN-β)- comes from fibroblasts.
3. Interferon -γ (IFN-γ) comes from immune cells.
There are three subtypes of IFN-α, namely IFN-α 1b, IFN-α2a and IFN-α2b, which are mainly used abroad, and IFN-α 1b is mainly used in China, which can be injected subcutaneously or intramuscularly, inhaled by atomization and used locally on skin and mucosa.
At present, genetically engineered interferons sold in China are divided into three subtypes according to their sources and molecular structures, namely α- 1B, α-2A and α-2B, among which α-2A and α-2B are imported products or domestic imitation products. Interferon α- 1b is a genetically engineered interferon cloned and expressed from white blood cells of healthy people in China. Many years' research by the Institute of Virology, Chinese Academy of Preventive Medicine shows that interferon α- 1b is the main interferon produced by the virus attack on human leukocytes in China. Therefore, compared with similar products at home and abroad, the efficacy of genetically engineered α- 1b interferon is remarkable (the remarkable efficiency is equivalent to that of foreign products).
The recombinant human interferon α 1b cloned and expressed by China gene has also become China's own interferon, which is more suitable for China. It is the first new drug of genetic engineering with independent intellectual property rights in China. Since 1996 was commercialized by Shenzhen Kexing, it has been widely used in pediatric field in China for more than 20 years, and accumulated a lot of literature and clinical experience. The antiviral effect of IFN-α 1b is mainly achieved by inducing cells to produce antiviral proteins and activating cellular immunity. The former activates JAK-STAT signaling pathway by binding with cell surface receptors, and induces the expression of many antiviral proteins such as 2', 5'- oligoadenylate synthetase (OAS), phosphodiesterase, protein kinase, etc., thus inhibiting virus replication in infected cells and protecting normal cells from virus invasion. The latter can eliminate the virus by enhancing the cellular immunity of the body, including promoting the proliferation of cytotoxic T lymphocytes (CTL), activating the killing activity of natural killer (NK) cells and phagocytosis of macrophages.
At present, interferon α 1b can be used clinically for bronchiolitis, viral pneumonia in children, herpetic angina in children, hand-foot-mouth disease in children, infectious diseases related to Epstein-Barr virus (EBV) in children, chronic hepatitis B in children, hepatitis C in children, rotavirus enteritis, viral encephalitis, measles, chickenpox and mumps.
Some interferon-α injections listed in China contain preservatives, such as methyl paraben, propyl paraben, benzyl alcohol and m-xylenol. Inhalation can induce asthma attack and should not be used for atomization treatment.
Therefore, the use of interferon-α injection containing preservatives should be avoided when inhaling interferon-α by atomization to reduce the damage and inflammation of respiratory mucosa.
Inhale interferon α by atomization, choose recombinant human interferon α injection or recombinant human interferon α for injection?
"Recombinant human interferon α injection" is liquid, and "Recombinant human interferon α for injection" is freeze-dried powder.
Suggestions on the treatment of patients with novel coronavirus infection by atomized inhalation indicate that atomized inhalation preparation should be selected. Intravenous preparations of non-atomized inhalation preparations often contain preservatives such as phenol and nitrite, which can induce asthma attacks after inhalation. The use of atomized inhalation treatment is beyond the instructions, and there is a great safety hazard. Therefore, the choice of dosage form is very important when inhaling interferon α by atomization.
The following figure shows the types of interferon and excipients from domestic manufacturers at present;
Some interferon-α injections on the market contain one or two preservatives (methyl nipagin, propyl nipagin, benzyl alcohol, m-xylenol, etc. ), are not suitable for atomizing inhalation.
Interferon α for injection in the market: the excipients are mostly albumin, mannitol and so on. No preservatives are added.
We should choose recombinant human interferon α for injection when inhaling interferon α by atomization, and avoid using interferon α injection containing preservatives to reduce the damage and inflammation of respiratory mucosa.
Which atomization method should be chosen for recombinant human interferon α in clinic?
Interferon α is a recombinant protein, and most accessories contain albumin, which may denature when heated. Both the jet atomizer and the vibrating screen hole atomizer meet the atomization requirements of protein drugs. Therefore, it is suggested that jet atomizer (air compression atomizer) and vibrating screen hole atomizer should be used for clinical interferon α atomization, and ultrasonic atomization is not recommended.